This is an application for a Clinical Site in response to RFA AG-94-002. We have studied the menopausal transition in a sample of 541 initially healthy women, predominantly middle- and upper middle-class. Although the number of African American women and women with a high school education or less were in the minority in our sample, they had unique characteristics at study entry and experienced unique changes during the follow-up period. We now propose to recruit 450 premenopausal women of middle and lower class socioeconomic status into a longitudinal study of the menopausal transition; 150 of them will be African American. Women will be evaluated at study entry and at 4 (perimenopause) and 12 months (postmenopause) after the cessation of menses. Matched by age and race to peri- and post-menopausal women, premenopausal women will be evaluated at the same time to serve as controls for aging, seasonality, and repeat testing. With this study design, we will evaluate the hypotheses that independent of aging, change in reproductive hormones, marked by cessation of menses, leads to alterations in levels of lipids and lipoproteins, susceptibility to lipid peroxidation; cardiovascular responses to behavioral challenge; carotid artery vessel compliance and distensibility; endothelial function in the brachial artery; bone mass of the proximal femur, lumbar spine, and total body calcium; body composition; production of pro-inflammatory cytokines; health behaviors; and rates of clinical episodes of depression or anxiety and levels of depressive symptoms. We will compare the magnitude of changes in the above according to race and social class, as measured by educational attainment, and will test specific hypotheses about the interrelationships among the changes, e.g. changes in bone and correlated with changes in cytokines; changes in cardiovascular responses to stress are related to changes in compliance, distensibility, endothelial function, and LDL oxidative susceptibility. Little is known about the menopausal transition, especially in Africa American women and women of lower socioeconomic status, and this proposal aims to supply important missing information.